Control apparatus



y 1941- E. c. RANEY 2,250,274 I CONTROL APPARATUS v Filed March 1, 19383 Sheets-Sheet 1 I 4 5L; 3 194 179 15 1;?

sariin gig/g INVEINTOR.

ATTORNEY.

y 1941- E. c. RANEY 2,250,274

CONTROL APPARATUS Filed March 1. 1938 3 Sheets-Sheet 2 INVENTOR July 22,1941, E. c. RANEY 2,250,274

GONTROL'APPARATUS Filed March 1, 1938 3 Sheets-Sheet 1 4 2 2 1 l 1 as O1 5 0 O 7 F/g ll 5 8\ s a 1 a '56 0 4 8 5 so 62- 10 1 as 5 4 8 1 is 1 68 I 1 1 s- I 18 ATTORNEY Patented July. 22, 1941 CONTROL APPARATUS EstelC. Raney, Columbus, Ohio, assignor to Ranco Incorporated, Columbus,Ohio, a corporation of Ohio Application March 1, 1938, Serial No.193,324

4 Claims.

This invention relates to control apparatus, and particularly totemperature control apparatus for household refrigerators.

An object of the invention is to provide a temperature responsive devicefor control apparatus comprising an expansible member having a tubeattached thereto, the tube and member being filled with a temperatureresponsive fluid, and a section of the tube being wound in a helix withanother section of the tube, whereby the adjacent convolutions of theresulting helix are of different sections of the tube so that arelatively lengthy portion of the capillary tube may be placed in arelatively short clamp, attached to the part of an apparatus controlledby the control device,

and the helix will be resistant to axial stresses.

Other and further objects and advantages will be apparent from thefollowing description, reference being had to the accompanying drawingswherein a preferred form of embodiment of the present invention isclearly shown.

In the drawings:

Fig. 1 is an enlarged view of the control apparatus taken on line I--Iof Fig.

Fig. 2 is a view of the apparatus taken on line 2-2 of Fig. 1;

Fig. 3 is a view of the apparatus taken on line 3-3 of Fig. 1;

Fig. 4 is a front view of the apparatus taken on line 44 of Fig. 1;

Fig. 5 is a rear view of the apparatus;

Fig. 6 is a view of the insulating block. showing the fixed contactmember and the toggle switch pivoting member mounted on the block;

Fig. '7 is a side view of Fig. 6;

b Fig. 8 is a view of the switch actuating mem- Fig. 9 is a partial viewof the member shown in Fig. 8;

Fig. 10 is a view taken on line I0--I0 of Fig. 3; I Fig. 11 is a partialview taken on line IIII of Fig. 2;

Fig. 12 is a side view of the frame member, with the insulating block inposition, and,

Fig. 13 is a view taken on line I3-I3 of Fig. 8.

A control apparatus similar to that described and claimed in mycopending application Serial Number 351,009, filed August 3, 1940, andindicated generally at 8, comprises a frame I0 preferably of a singlesection of sheet metal formed in a U shape, forming a front wall I4 andside walls I6 for supporting and inclosing the control mechanism. Theside walls I6 each have a laterally extending flange I8, which isprovided with two openings 22, at either end thereof, for connecting apower element 24 to the frame.

The power element 24, in the present form of disclosure, consists of ametal bellows 20 enclosed within a shell 26 and having a closed tube 2tconnected thereto. ihe bellows and tube are filled with a thermalresponsive fluid, such as methyl chloride, so that the fluid pressurewill cause variations in pressure within the bellows according to thevariations of temperatures to which a part of the tube is subjected. Asection of the tube 2| adjacent the end thereof is reversed as at H andthe doubled tube then formed into a closely wound helix as shown at I9.

The helix I0 may then be secured to the evaporator of a refrigeratorapparatus by a thermal conducting clamping device (not shown) at tachedto the evaporator. Such clamping devices are cylindrical in form andtightly embrace the helix so that the temperature of the helix willcorrespond to the temperature of the evaporator. The helix providesmeans for presenting a lengthy section of tube for contact with theclamp so that a relatively large volume of the enclosed fluid will beaffected by the temperatures in the evaporator. It will be noted thatevery other convolution of the helix is formed of the reversed sectionof the tube, thereby reenforcing the helix against axial stress whichmay be caused by accidental pulling of the tube.

A push rod 23 is connected to the movable end of the bellows 20 andengages a switch actuating member 50 for actuating the switch by theexpansion and contraction of the bellows 20, as will be described later.The shell 26 is provided with a flange 28, having squared cornersthereon which register with the corners of the flanges I8. Openings areprovided adjacent each corner of the flange, which register with theopenings 22 in the flanges I8, and the shell 26 is connected to theframe I0 by rivets 32. Thus the power element 24 provides a rigidreinforcing base for maintaining the side walls rigid.

A toggle switch mechanism is mounted on a block I02 preferably formed ofa dielectric material, such as Bakelite, and the block is attached tothe frame I0 between the side walls IS. The block I02 is formed with twooppositely disposed side walls I50 which are adapted to fit between theside walls I6 of the frame I0, and maintain the walls rigidly spacedfrom one another. A pair of bosses I48 are formed on the side walls I50and are adapted to engage the edges of the side walls I6 for locatingthe block with respect to the edges of the walls.

The side walls are formed ears which, after tlle block W2 is inserted inposition, are turned to conform to the curved corners of walls I46,formed on the insulating block. When the ears I52 are turned, the insideedges engage shoulders I44 formed at each corner of the block I02. Thusthe block is locked in engagement with the side walls I6 of the frameit. The bosses I46 are adapted to engage in a shallow offset I49, formedin the edge of the side walls I6 to prevent movement of the block withrespect to the upper and lower edges of the side walls. Thus theinsulating block I02, carrying the switch mechanism may be easily andsecurely attached to the frame, further reenforcing the walls andforming a closing wall for the control apparatus.

A U shaped bracket I04 is secured to the insulating block I02 by rivetI03 extending through the yoke and block. The legs of the U shapedbracket I04 are provided with two pairs of V shaped notches or pivotsI06 and N1 for pivoting the ends of a pair of toggle members therein.The pivots I06 are oifset with respect to the pivots I01 and aredisposed closer to the block I02 for reasons which will appearhereinafter. The moving parts of the switch mechanism comprises two Ushaped toggle members I06 and H0, which are preferably formed of sheetmetal stampings and reenforced by the upturned edges III and I I2respectively. The ends of the legs of each of the members I08 and H areadapted to engage in the pivots I06 and I0! respectively, and areyieldingly retained in their respective pivots by a tension spring I09,connected in holes II3 formed in the yoke of the members, and carriedbetween the legs thereof. The ends of the legs of the members arebeveled to form knife edged bearings. The yoke of the member I08 has asemicylindrical section I I6 formed therein for reenforcing the memberand to allow space for the spring I 09 to move between the legs thereof.The member H0 is adapted to carry an insulating member or strip 6,preferably of fiber, on the free end thereof. The strip H6 is connectedto the member IIO by three ears I22, formed on the member IIO, two ofwhich are crimped over the side edges of the strip and the third ofwhich extends through an opening in the strip and is crimped over thesurface of the strip adjacent the opening. A contact bar I I6 is securedon the end of the strip H6 and is adapted to bridge a pair of fixedcontacts I32 mounted on the insulating block I02. A T shaped opening II!is provided in the strip I I 6 through which a part of the contact barII8 extends. preferably formed of a copper sheet having the eneral shapeof a triangle, having 9. lug I2I formed at the apex and a similar lugI23 formed at the center of the base thereof. The sheet is looselyformed over the end of the member II6 as shown in Fig. 1, and the lug I23 is turned to extend into one end of the opening II! for holding thecontact member H6 in place on the strip. A pair of contacts I20 areriveted to the wide part of the contact member I I6, and are spaced toenage the fixed contacts I32 when the switch is closed. The contacts I32are suitablymounted each on one of a pair of terminal bars I30 rivetedto the block. The circuit wires for the device to be controlled may beconnected to the terminal members I30, by terminal screws I34 threadedin the terminal members from the opposite side of the insulating blockthrough suitable openings in theblock. A chamber I36 is formed in theblock I02 by walls I46 for accommodating the The contact bar H6 is wireleads from the circuit. A plate i333, preferably of insulating material,is provided for inclosing the chamber. The plate H8 is secured over thechamber opening by screws 562, which are threaded in a pair of bushings540, formed integral with the insulating block 502. The bushn s I40serve as supports for. the cover. The plate I30 i provided with anopening Hi to admit the line wires to the chamber I36. Thus the switchmechanism may be completely assembled on the insulating block I02, andthe block then secured to the walls of the frame, as a unit.

The switch mechanism is adapted to be operated by the power element 24through the switch actuating member 60. The member 60 is preferablyformed of heavy sheet metal and comprises a base 62 and an arm 64 formedintegral therewith, and is pivotally supported between the side walls I6by a pin 66. The pin 66 is tightly pressed in holes 61 and 66, formed inan upturned ear 60 of the base 62 and at the base of the arm 64,respectively, so that the pin 66 is substantially an integral part ofthe actuating member 60. The length of the Pin 66 is such that arelatively short section of the pin will extend beyond either side ofthe member 60 when the pin is in place. The side walls I6 each have acircular indentation 62, formed therein, each of which is provided witha bearing 63 for receiving an end of the pin 66. The bearings 63 areformed by lancing a circular opening in the indented part of the wall sothat the metal adjacent the opening is extended to present a substantialbearing surface. Thus the ends of the pin 66 may extend through thebearings 63, without extending beyond the plane of the surface of theside walls I6. In the assembly of the control device, the actuatingmember 60 is secured in position between the walls of the fr .2 I0 priorto the connection of the power element 24 to the frame so that the wallsmay be spread and the ends of the pin 66 slipped into the bearing 63.When the power element is attached to the frame, the walls are then heldrigid, and the pin 66 will be locked in the bearings. The arm 64 isprovided with fingers 64 and 61 formed at the end thereof. The fingersare provided with 9. lug 66 and an engaging screw 66 which engage thetoggle member I08 when the switch is oper ated. The screw 66 is adaptedto be held between a member 66, riveted to the arm 64, and the finger64. The member 66 and the finger 64 are each formed with curved portionsI0 and TI respectively for receiving the adjusting screw 66. The member66 is preferably formed of resilient material so that the screw 66 willbe pressed in the curved sections I0 and II for preventing change in theadjustment of the screw. The arm 64 is provided with 0. lug 6I formedthereon for engaging the switch member IIO for limiting the openingmovement of the switch member. The base 62 of the member 60,-has one endupturned, as at I2, which is formed with a neck 14 and shoulders 16. Awasher I6, having an opening 11 of substantially the same shape as thecross section of the neck I4, is loosely carried on the shoulders I6,and held on the neck I4 by mutilations I6 at the top of the neck. Thewasher 16 has a circular embossed part 60 for centering a compressionspring I60 thereon. A screw 64 having an indented part (not shown) inone end thereof for receiving the end of the thrust rod 23, is threadedin a lanced opening 62, formed in the base 62. The screw 84 is locked inposition by a lock washer 66 after it is once adjusted to a properoperating position with respect to the push rod 23. An arm 90, formed onthe member 50 extends at substantially right angles with the arm 54, andis adapted to move in a rectangular opening 92, formed in the front wallI4 for limiting the movement of the actuatin member 50 within a definiterange to prevent distortion of the parts of the control apparatus if thehelix I9 should be subjected to warm atmospheric temper- I atures.

When the block I02 with the toggle switch mechan'sm assembled thereon isattached to the frame 0, the yoke of the toggle member I06 is first slidbetween the fingers 64 and 61 of the arm 54 and the block N2 is thensecured to the side walls I6 as described above. Thus the actuatingmember 50 is adapted to engage the member I08 and move it about itspivot to operate the switch, as will be described hereinafter.

The top of, the frame is closed, after the block I02 is attachedthereto, by a cover I90 having one end of the cover turned at rightangles and the end edge of the turned portion shaped to conform with thetop side of the block I02 toefiectively enclose the switch apparatus inthe frame. v The cover I90 is formed with turned edges I9I, which fitover the ends of the frame walls, and detents I93 are provided in theedges I9I, which engage with similar detents I94 formed in the sidewalls I6 adjacent the top thereof for frictionally holding the cover onthe frame.

The spring I60 is provided for controlling the temperatures at which theswitch is operated. One end of the spring I60 is adapted to engage thewasher 16, as described above, and thereby transmit a load on thebellows through the member 50. The other end of the spring is engaged bya plate I62, having a circular centering boss I63 and a threaded holeI64 through the center thereof for receiving a screw I66. The plate isformed with a pair of ears I65, which engage the wall of a slide ormember I68, to prevent rotation of the plate. The plate is connected tothe slide I 68 by the screw I66, which is threaded in the hole I64, andsupported on a bracket I61 formed on the slide. The bracket I61 isprovided with a hole through which the screw I66 is extended and rigidlyfixed thereto by a nut I10 and washer I1I. Thus the spring I60 may beadjusted at the factory by turning the screw I66 one way or the other tochange the distance of the end of the spring I60 from the bracket I61and establish the proper adjusting range of the control apparatus by theuser thereof.

The slide 866 is formed of sheet metal and comprises a wall part havinga turned end which comprises the bracket I61. The bracket and wall partare reenforced by web parts E61 formed thereon. A lug I12 is rivetedadjacent one end of the wall part of the slide I 68 and extends througha slit E15 formed in the wall M for enagernent with the periphery of acam I16. The ing is cylindrical in shape and is provided with a flange915 on the end thereof which engages the outside surface of the cam I16to hold the adjusting member M8 against the wall It. The spring I60yieldingly engages the lug I12 with the De" riphery of the cam. Thewidth of the slide I68 is such that the sides thereof engage the wallsI6 and when the slide is moved by the cam, the walls uide the member ina direction of the axis of the spring I60.

The cam I16 includes a hub I82 formed integral therewith which isadapted to be axially supported on a post I18 secured to the wall It,such as by extending a hollowed neck part on the post through a hole inthe wall I4 and then rolling the neck outwardly and against the wall asindicated at i". A slot I19 is provided in the wall part of the slideI68 to accommodate the turned part I11 and permit the slide I68 to moveagainst the inside surface of the wall I4. The hub I82 is square incross section so that a knob I86 provided with a squared recess may befitted on the hub whereby the cam can be rotated by the knob. Circulargrooves are provided adjacent the end of the hub I82 and in the recessin the cap, so that a split ring spring I80 may be interposed betweenthe two grooves and thereby hold the knob'on the shaft.

When the cam I16 is rotated by the knob, the periphery thereof is inengagement with the lug I12, and translates the slide I66 in a directionof the axis of the spring I60. The cam I16 is provided with detents I81on the periphery thereof which are adapted to engage the lug I 12 andlimit the rotation of the cam member in either direction. Thus when itis desirable to increase the pressures or temperatures at which theswitch is operated the cam is rotated counterclockwise, as viewed inFig. 4, which moves the slide I68 downwardly thereby compressing thespring I60, to increase load upon the bellows. When it is desired todecrease the pressures or temperatures at which the switch operates, the

cam is rotated clockwise which permits the spring I60 to raise the slideI68 upwardly and decrease the tension of the spring I60.

therein causes expansion of the bellows 20 to rotate the member 50'clockwise, as viewed in Fig. 1. The finger 64 is in engagement with themember I 08 and the lug 6| is in engagement with themember III), andthese two members are moved to the right and about their pivots I06 andI01. The pivots I06 and I01 are offset from one another as describedabove, so that the center of the spring I09 will pass to the right ofthe pivot I01 prior to passing to the right of pivot I06, and in sodoing will cause the member IEO to be snapped to the switch closingposition, which causes the spring I09 to pass to the right of pivot I06and snap the member E08 against the screw 66. The refrigeratingapparatus is thus energized and the coil I9 will then be cooled andcause the gas pressure in the bellows 29 to decrease. The spring I60will then cause the member 50 to be rotated counterclockwise and thefinger 61 will move the member I08 and the spring N39 to the left of thepivot I86 and cause the member I68 to be snapped to the ing 65. Thespring 508 is then carried to the left of the pivot I01 and snaps themember IIS against the stop M on the arm 5 3 to open the switch anddeenergize the refrigerating apparatus.

The control apparatus may be attached to the refrigerator by a sheetmetal bracket I19 secured.

post I16 extends. Holes are provided adjacent rature responsive elementincludng tube, a section of said upon itself and said reversed adjacenttube section being formed he ccnvolntions of the helix substaning oneanother.

'ecsnre responsive member; a tube connected neemizer, said tube having asection thereof reversed upon another section of the tube and having thetwo sections formed in a helix, the convolutions of the helix beingrelatively close to one another.

3. A temperature responsive device, including a pressure responsivemember; a tube connected to the member, said tube having a. sectionthereof formed in a helix, and the convolutions of the said helix havinganother section of the tube interposed there between for reenforcing thesaid helix against axial stresses.

4. A temperature responsive device, including a pressure responsivemember; a tube connected to the member, the said tube having a sectionhereof formed in a helix, and the convolutions of the helix having ahelical formed member interposed therebetween for. reenforcing the saidhelix against axial stresses.

'E STEL C. RANEY.

